commensalism

American  

[kuh-men-suh-liz-uhm] / kəˈmɛn səˌlɪz əm /

noun

1. Ecology. a type of relationship between two species of a plant, animal, fungus, etc., in which one lives with, on, or in another without damage to either.

2. Sociology. peaceful coexistence among individuals or groups having independent or different values or customs.

---

commensalism Scientific  

/ kə-mĕn′sə-lĭz′əm /

1. A symbiotic relationship between two organisms of different species in which one organism derives benefit while the other is unaffected. Examples of commensalism include epiphytic plants, which depend on a larger host plant for support but which do not derive any nourishment from it, and remoras, which attach themselves to sharks and feed on their leavings without appreciably hindering their hosts.

2. Compare amensalism mutualism parasitism

---

Usage

What does commensalism mean? Commensalism is a relationship between two species of organisms, such as plants, animals, and fungus, in which one species benefits while the other is unaffected, as in Scientists have studied the commensalism of fleas that feed on birds’ feathers. A well-known example of commensalism is the relationship between the remora, commonly known as a suckerfish, and a shark. The  remora uses its suction cup–like head to attach itself to a shark. The remora benefits from the speed, protection, and leftover food from the shark. The shark gets nothing from the remora. It isn’t hurt by the remora, but the remora doesn’t help the shark in any way. You can think of commensalism as a “+/0” relationship: One species benefits while the other remains the same. This is what sets commensalism apart from the other types of relationships between organisms, such as mutualism, parasitism, and amensalism. In mutualism, both species benefit from the relationship. For example, a bird might pick food out of the teeth of an alligator, which prevents the teeth from becoming infected. Mutualism is a “+/+” relationship because the bird gets food to eat and the alligator gets cleaner teeth. In parasitism, one species (the parasite) benefits at the expense of the other species, a “+/-” relationship. For example, when a  mosquito bites you, it has drunk some of your blood, which nourishes it. You, however, get an itch bite and possibly a disease carried by mosquitoes, such as Eastern equine encephalitis (EEE). In amensalism, one species harms another species while remaining unaffected, a “-/0” relationship. For example, the black walnut tree secretes a substance that is harmful to other plants. The tree isn’t harmed by either the substance or the other plants.

Etymology

Origin of commensalism

commensal + -ism

Compare meaning

How does commensalism compare to similar and commonly confused words? Explore the most common comparisons:

• mutualism vs. commensalism

Explanation

If you've ever seen a bunch of barnacles attached to a great big whale, you've seen an example of commensalism, or one organism getting benefits from another without hurting it. First used in a biological sense in 1870, commensalism originates from the Middle Latin word commensalis, derived from com ("together") and mensa ("table"). It's a relationship between two organisms in which one receives benefits without causing harm. Commensalism should not be confused with mutualism, a relationship in which both organisms benefit from each other.

Example Sentences

However, how gut fungal commensals affect immunity is less well understood, due in part to the lack of a good mouse model of fungal commensalism.

From Science Daily • Nov. 27, 2024

This is commensalism, because bees obtain nectar from the plants, but do not provide any benefits to the plants.

From Textbooks • Jun. 9, 2022

Species may form symbiotic relationships such as commensalism or mutualism.

From Textbooks • Jun. 9, 2022

Species may form symbiotic relationships such as commensalism, mutualism, or parasitism.

From Textbooks • Sep. 6, 2018

Among many remarkable qualities they have been distinguished from the earliest times by a species of commensalism, or power of living among other nations without becoming either socially merged or politically distinct.

From Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 7 "Arundel, Thomas" to "Athens" by Various